1. Field of the Invention
The present invention relates to an image forming apparatus, such as an electrophotographic copying machine, which can perform a double-sided copying operation, and more particularly to an image forming apparatus which conveniently removes recording medium from the image forming apparatus when a double-sided copying operation is cancelled.
2. Description of the Related Art
Recently, image forming devices such as electric copying machines which can perform a double-sided copying operation are generally known. For example, U.S. Pat. No. 4,970,555 discloses a copying machine which can perform a double-sided copying operation. This copying machine includes a double-sided copying unit for reconveying a paper sheet to an image transfer position to perform the double-sided copying operation. The double-sided copying unit includes a stacking portion for temporarily stacking paper sheets having an image formed on one side before completing the double-sided copying operation.
In conventional copying machines, for example, if the double-sided copying mode is changed or cancelled while paper sheets are stacked in the stacking portion of the double-sided copying unit, the paper sheets remain in the stacking portion of the double-sided copying machine. It is then a necessary inconvenience for a user to open a front cover, or perform a blank copying operation, to remove the paper sheets from the stacking portion.
In order to solve this problem, Japanese Patent Disclosure (Kokai) No. 58-57143 discloses a copying machine having an ejecting device for ejecting paper sheets stacked in the stacking portion and an output tray for receiving the paper sheets ejected by the ejecting device. It is not necessary in this copying machine to open a front cover or perform a blank copying operation to remove paper sheets from the stacking portion. However, the ejecting device and the output tray increases the size and cost of the copying machine when there is presently a need to reduce the size and costs of copying machines. Moreover, this prior art reference does not describe the operation for ejecting paper sheets from the stacking portion.